Celtic sea saltsel de guerande is hand harvested on the celtic sea coast in brittany it is a nationally preserved area and registered as a world heritage site since 2002the salt is obtained by sun and wind evaporation and it is neither filtered nor cleaned thus it is free of pollutants from mechanical and chemical processesit contains bio available minerals and trace elements calcium potassium magnesium iron manganese sulphur zinc and other nutritive elementsthis is why it is grey